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Paul Helliker had a job for Dow AgroSciences.

As director of the California Department of Pesticide Regulation, Helliker had allowed some growers to ignore the restrictions for a pesticide called 1,3-Dichloropropene, which the state believed caused cancer.

The loophole was supposed to be temporary. Helliker gave Dow, the company that manufactures 1,3-D, and growers two years to come up with a plan to follow his department’s rules or to create new ones.

It took Dow less than a year to hand in its proposal. The company’s plan didn’t close the loophole, however. It greatly expanded it.

Dow asked that the director allow growers across the state to use twice as much 1,3-D in a year as the rules permitted. And the company wanted it to happen quickly. Two Dow officials, Bryan Stuart and Bruce Houtman, closed their proposal by saying that “implementation will begin immediately upon receipt of approval” from Helliker.

Six days later, Helliker signed off on the heart of Dow’s plan.

With that simple memo in 2002, Helliker dismantled the strict oversight designed seven years earlier to protect Californians from cancer, opening the door to 12 years of nearly unfettered 1,3-D access as its use spread to populated areas near schools, homes and businesses.

The decision put people in more than 100 California communities at a higher risk of cancer, according to interviews with former state scientists and documents obtained by The Center for Investigative Reporting. The system of exemptions, which has continued under two subsequent directors, runs counter to the department’s stated mission to protect the well-being of California residents.

Joseph Frank, a retired state toxicologist whose team evaluated human exposure to 1,3-D, said people in those communities should demand answers.

“They should ask their representatives, ‘Why?’ ” he said. 

The loophole also expanded a key market for Dow, allowing it to sell millions more pounds of chemicals across a state that provides the United States with nearly half of all its fruits, vegetables and nuts.

The chemical is the third most heavily used pesticide in California.

California has a long and tortured relationship with 1,3-D, a byproduct of plastic manufacturing that’s often sold under the brand name Telone.

In 1990, the state suddenly pulled 1,3-D from the market after learning how much lingered in the air near farm fields in the Central Valley. After five years and $5 million of research, Dow persuaded the state to allow it back on the market with severe restrictions.

In response to questions from CIR, Dow said no agricultural uses of 1,3-D pose any cancer risk. And the company said it has new research that shows the existing limits are too conservative.

In an interview, Helliker maintained that his decision to alter the pesticide policy in 2002 didn’t put Californians in danger. Because the state’s regulations average cancer risk over a lifetime, Dow and state regulators said, it’s fine for people to be exposed to more 1,3-D in some years as long as it evens out over time.

Helliker said he can’t recall whether department scientists disagreed with his decision. But documents obtained by CIR show a state toxicologist objected to the science – and the logic – as soon as Dow began raising the idea in 2001.

Eight years later, a new batch of department leaders received similar warnings from another staff scientist. Toxicologist Linda Hall disputed the basic justification Dow and Helliker used to create the loophole.

“Department of Pesticide Regulation (DPR) scientists do not agree and suggest that this practice may actually increase cancer risk,” she wrote.

Still, department leaders didn’t put a stop to it.